Day 1 - AWS CDK Environment Setup and First Steps

Today's Goals

1. Set up AWS CDK development environment
2. Create your first CDK project
3. Deploy a simple S3 bucket
4. Understand basic CDK commands

1. Environment Setup

1.1 Node.js Installation Check

AWS CDK runs on Node.js. First, let's check the current version.

node --version
npm --version

Node.js 18.x or higher is required. If not installed, download from the Node.js official website.

1.2 AWS CLI Setup

AWS CDK uses AWS CLI to communicate with your AWS account.

# Check AWS CLI version
aws --version

# Configure AWS credentials
aws configure

Enter the following information:

• AWS Access Key ID
• AWS Secret Access Key
• Default region name (e.g., ap-northeast-1)
• Default output format (json recommended)

1.3 AWS CDK Installation

Install AWS CDK globally.

npm install -g aws-cdk

After installation, check the version.

cdk --version

1.4 CDK Bootstrap

Before using CDK, you need to run bootstrap for your AWS account and region.

cdk bootstrap

This creates resources that CDK uses, such as S3 buckets and IAM roles.

2. Creating Your First Project

2.1 Create Project Directory

mkdir my-first-cdk-app
cd my-first-cdk-app

2.2 Initialize CDK Application

Initialize a new CDK app using TypeScript template:

cdk init app --language typescript

This creates the following project structure:

my-first-cdk-app/
├── bin/
│   └── my-first-cdk-app.ts     # App entry point
├── lib/
│   └── my-first-cdk-app-stack.ts # Stack definition
├── test/
│   └── my-first-cdk-app.test.ts  # Unit tests
├── cdk.json                     # CDK configuration
├── package.json                 # npm dependencies
└── tsconfig.json               # TypeScript configuration

2.3 Install Dependencies

npm install

3. Understanding the Basic Structure

3.1 App Entry Point (bin/my-first-cdk-app.ts)

#!/usr/bin/env node
import 'source-map-support/register';
import * as cdk from 'aws-cdk-lib';
import { MyFirstCdkAppStack } from '../lib/my-first-cdk-app-stack';

const app = new cdk.App();
new MyFirstCdkAppStack(app, 'MyFirstCdkAppStack', {
  env: {
    account: process.env.CDK_DEFAULT_ACCOUNT,
    region: process.env.CDK_DEFAULT_REGION,
  },
});

3.2 Stack Definition (lib/my-first-cdk-app-stack.ts)

import * as cdk from 'aws-cdk-lib';
import { Construct } from 'constructs';

export class MyFirstCdkAppStack extends cdk.Stack {
  constructor(scope: Construct, id: string, props?: cdk.StackProps) {
    super(scope, id, props);

    // Your resources will be defined here
  }
}

4. Creating Your First S3 Bucket

4.1 Modify Stack to Add S3 Bucket

Edit lib/my-first-cdk-app-stack.ts:

import * as cdk from 'aws-cdk-lib';
import * as s3 from 'aws-cdk-lib/aws-s3';
import { Construct } from 'constructs';

export class MyFirstCdkAppStack extends cdk.Stack {
  constructor(scope: Construct, id: string, props?: cdk.StackProps) {
    super(scope, id, props);

    // Create an S3 bucket
    const bucket = new s3.Bucket(this, 'MyFirstBucket', {
      bucketName: 'my-first-cdk-bucket-' + Math.random().toString(36).substring(7),
      versioned: true,
      removalPolicy: cdk.RemovalPolicy.DESTROY,
      blockPublicAccess: s3.BlockPublicAccess.BLOCK_ALL,
    });

    // Output the bucket name
    new cdk.CfnOutput(this, 'BucketName', {
      value: bucket.bucketName,
      description: 'The name of the S3 bucket',
    });
  }
}

4.2 Key Properties Explained

• bucketName: Unique bucket name (with random suffix)
• versioned: Enable object versioning
• removalPolicy: What to do when stack is deleted (DESTROY allows deletion)
• blockPublicAccess: Security setting to block all public access

5. CDK Commands

5.1 Synthesize CloudFormation Template

cdk synth

This generates the CloudFormation template and displays it. You can see how your CDK code translates to CloudFormation.

5.2 Compare Changes

cdk diff

Shows the differences between your current stack and the deployed stack.

5.3 Deploy the Stack

cdk deploy

This deploys your stack to AWS. You'll be prompted to confirm the changes before deployment.

5.4 List All Stacks

cdk list

Shows all stacks in your CDK app.

5.5 Destroy the Stack

cdk destroy

Deletes the stack and all its resources from AWS.

6. Exercise: Create Multiple Resources

Try adding more resources to your stack:

6.1 Add Another S3 Bucket with Website Hosting

// Add to your stack
const websiteBucket = new s3.Bucket(this, 'WebsiteBucket', {
  bucketName: 'my-website-bucket-' + Math.random().toString(36).substring(7),
  websiteIndexDocument: 'index.html',
  websiteErrorDocument: 'error.html',
  publicReadAccess: true,
  removalPolicy: cdk.RemovalPolicy.DESTROY,
});

new cdk.CfnOutput(this, 'WebsiteURL', {
  value: websiteBucket.bucketWebsiteUrl,
  description: 'Website URL',
});

6.2 Deploy and Test

# See what will be created
cdk diff

# Deploy the changes
cdk deploy

Check the AWS Console to see your created resources.

7. Best Practices for Day 1

7.1 Naming Conventions

• Use descriptive names for constructs
• Include environment or purpose in resource names
• Use consistent naming patterns

7.2 Resource Management

• Always set removalPolicy for development resources
• Use blockPublicAccess for S3 buckets unless public access is needed
• Add meaningful outputs for important resource properties

7.3 Code Organization

• Keep stack files focused and not too large
• Use comments to explain complex configurations
• Follow TypeScript best practices

8. Troubleshooting Common Issues

8.1 Bootstrap Issues

If bootstrap fails:

# Check AWS credentials
aws sts get-caller-identity

# Try bootstrapping with explicit region
cdk bootstrap aws://ACCOUNT-NUMBER/REGION

8.2 Bucket Name Conflicts

S3 bucket names must be globally unique. If deployment fails:

• Use random suffixes as shown in examples
• Include timestamp or account ID in bucket names

8.3 Permission Issues

Ensure your AWS user has sufficient permissions:

• CloudFormation full access
• IAM permissions for creating roles
• Permissions for services you're using (S3, Lambda, etc.)

Summary

Today you learned:

1. ✅ Set up AWS CDK development environment
2. ✅ Created your first CDK project
3. ✅ Deployed an S3 bucket using CDK
4. ✅ Understood basic CDK commands and workflow

Key Concepts Covered

• CDK Bootstrap: One-time setup for CDK in your AWS account
• Constructs: Building blocks of CDK applications
• Stacks: Units of deployment in CDK
• Synthesis: Converting CDK code to CloudFormation templates

Next Steps

Tomorrow (Day 2), we'll dive deeper into CDK constructs and explore more AWS services like Lambda and API Gateway.

---

Exercise Solution:

Complete stack with multiple resources:

import * as cdk from 'aws-cdk-lib';
import * as s3 from 'aws-cdk-lib/aws-s3';
import { Construct } from 'constructs';

export class MyFirstCdkAppStack extends cdk.Stack {
  constructor(scope: Construct, id: string, props?: cdk.StackProps) {
    super(scope, id, props);

    // Private bucket for data storage
    const dataBucket = new s3.Bucket(this, 'DataBucket', {
      bucketName: 'my-data-bucket-' + Math.random().toString(36).substring(7),
      versioned: true,
      removalPolicy: cdk.RemovalPolicy.DESTROY,
      blockPublicAccess: s3.BlockPublicAccess.BLOCK_ALL,
    });

    // Public bucket for website hosting
    const websiteBucket = new s3.Bucket(this, 'WebsiteBucket', {
      bucketName: 'my-website-bucket-' + Math.random().toString(36).substring(7),
      websiteIndexDocument: 'index.html',
      websiteErrorDocument: 'error.html',
      publicReadAccess: true,
      removalPolicy: cdk.RemovalPolicy.DESTROY,
    });

    // Outputs
    new cdk.CfnOutput(this, 'DataBucketName', {
      value: dataBucket.bucketName,
      description: 'Name of the private data bucket',
    });

    new cdk.CfnOutput(this, 'WebsiteURL', {
      value: websiteBucket.bucketWebsiteUrl,
      description: 'Website URL',
    });
  }
}